Guiding introducer system for use in medical procedures in the left ventricle

ABSTRACT

A guiding introducer system for use in the treatment of arrhythmia associated with the left ventricle from the ventricular side comprising an inner guiding introducer and an outer guiding introducer wherein the inner guiding introducer is comprised of a first and second section and the outer guiding introducer is comprised of a first and second sections. The guiding introducer system is for use in sensing, pacing, and ablating procedures in the left ventricle.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.09/728,961 titled “Guiding Introducer System for Use in MedicalProcedures in the Left Ventricle,” filed on Dec. 4, 2000; which is acontinuation of application Ser. No. 09/160,406 titled “GuidingIntroducer System for Use in Medical Procedures in the Left Ventricle,”filed on Sep. 25, 1998 and issued on Dec. 5, 2000 as U.S. Pat. No.6,156,018; which is continuation of application Ser. No. 08/661,094titled “Guiding Introducer System for Use in Medical Procedures in theLeft Ventricle,” filed on Jun. 10, 1996 and issued on Sep. 29, 1998 asU.S. Pat. No. 5,814,029; which is a continuation-in-part of applicationSer. No. 08/388,800 titled “Guiding Introducers for Use in the Treatmentof Accessory Pathways around the Mitral Valve using the RetrogradeApproach,” filed on Feb. 14, 1995 and issued on Jun. 24, 1997 as U.S.Pat. No. 5,640,955, and a continuation-in-part of application Ser. No.08/389,252 titled “Guiding Introducers for use in the Treatment of LeftVentricular Tachycardia,” filed on Feb. 16, 1995 and issued on Mar. 3,1998 as U.S. Pat. No. 5,772,400, and a continuation-in-part ofapplication Ser. No. 08/333,791 titled “Method for Mapping and/orAblation of Anomalous Conduction Pathways,” filed Nov. 3, 1994 andissued on Oct. 15, 1996 as U.S. Pat. No. 5,564,440, and acontinuation-in-part of application Ser. No. 08/333,759 titled “GuidingIntroducer System for Use in the Right Atrium,” filed on Nov. 3, 1994and issued on May 13, 1997 as U.S. Pat. No. 5,628,316; the disclosure ofeach of the above-referenced related applications and patents are herebyincorporated be reference in their entirety as thou fully set forthherein. This application is also related to U.S. Pat. Nos. 5,497,774 and5,427,119, the disclosures of which are hereby incorporated by referencein their entirety as though fully set forth herein.

BACKGROUND OF INVENTION

1. Field of Invention

This invention relates to sheaths or introducers. More particularly,this invention relates a guiding introducer system for mapping andablation procedures in the left ventricle of the human heart.

2. Prior Art

Introducers and catheters have been in use for medical procedures formany years. For example, catheters have been used to convey anelectrical stimulus to a selected location within the human body.Another use is monitoring and making measurements for diagnostic testswithin the human body. Catheters are also used by physicians to examine,diagnose and treat while positioned at a specific location within thebody which is otherwise inaccessible without more invasive procedures.In use, catheters are inserted into a major vein or artery which is nearthe body surface. These catheters are then guided to the specificlocation for examination, diagnosis or treatment by manipulating thecatheter through the artery or vein of the human body.

Catheters have become increasingly useful in remote and difficult toreach locations within the body. However, the utilization of thesecatheters is frequently limited because of the need for the preciseplacement of the electrodes of the catheter at a specific locationwithin the body.

Control of the movement of catheters to achieve such precise placementis difficult because of the inherent structure of a catheter. The bodyof a conventional catheter is long and tubular. To provide sufficientcontrol of the movement of the catheter, it is necessary that itsstructure be somewhat rigid. However, the catheter must not be so rigidas to prevent the bending or curving necessary for movement through thevein, artery or other body part to arrive at the specified location.Further, the catheter must not be so rigid as to cause damage to theartery or vein while it is being moved within the body.

While it is important that the catheter not be so rigid as to causeinjury, it is also important that there be sufficient rigidity in thecatheter to accommodate torque control, i.e., the ability to transmit atwisting force along the length of the catheter. Sufficient torquecontrol enables controlled maneuverability of the catheter by theapplication of a twisting force at the proximal end of the catheter thatis transmitted along the catheter to its distal end. The need forgreater torque control often conflicts with the need for reducedrigidity to prevent injury to the body vessel.

Catheters are used increasingly for medical procedures involving thehuman heart. In these procedures a catheter is typically advanced to theheart through veins or arteries and then is positioned at a specifiedlocation within the heart. Typically, the catheter is inserted in anartery or vein in the leg, neck, upper chest or arm of the patient andthreaded, generally with the aid of a guidewire and conventionalintroducer, through various arteries or veins until the tip of thecatheter reaches the desired location in the heart.

The distal end of a catheter used in such a procedure is sometimespreformed into a desired curvature so that by torquing the catheterabout its longitudinal axis, the catheter can be manipulated to thedesired location within the heart or in the arteries or veins associatedwith the heart. For example, U.S. Pat. No. 4,882,777 discloses acatheter with a complex curvature at its distal end for use in aspecific procedure in the right ventricle of a human heart. U.S. Pat.No. 5,231,994 discloses a guide catheter for guiding a balloon catheterfor the dilation of coronary arteries. U.S. Pat. No. 4,117,836 disclosesa catheter for the selective coronary angiography of the left coronaryartery and U.S. Pat. Nos. 5,299,574 5,215,540, 5,016,640 and 4,883,058disclose catheters for selective coronary angiography of the rightcoronary artery.

Conventionally, angiographic or balloon catheters are guided to theparticular location within the heart, such as the coronary arteries, byuse of a guidewire. During this procedure, the guidewire is firstintroduced into the vein or artery and is then advanced through thevasculature to the particular coronary artery to be analyzed. Thecatheter is then directed over the guidewire to the particular coronaryartery. A conventional short straight introducer is often used to assistin introducing the coronary catheter into the vasculature, but is notused for advancing the coronary catheter through the vasculature to thecoronary artery.

U.S. Pat. No. 5,242,441 discloses a deflectable catheter for ablationprocedures in the ventricular chamber. See also U.S. Pat. No. 4,033,331.In addition, U.S. Pat. No. 4,898,591 discloses a catheter with inner andouter layers containing braided portions. The '591 patent also disclosesa number of different curvatures for intravascular catheters.

Thus, catheters with predetermined shapes, designed for use duringspecific medical procedures generally associated with the heart or thevascular system have been disclosed.

In addition to single catheters with various curvatures, U.S. Pat. No.4,581,017 discloses an inner and outer guide catheter, numbers 138 and132, for use with a balloon catheter for treatment of coronary arteries.U.S. Pat. No. 5,120,323 discloses a guide catheter system for use incoronary arteries comprising an outer guide catheter (12) and atelescoping guide catheter (26), neither of which are precurved. U.S.Pat. No. 5,267,982 discloses a catheter assembly and methods forcatheterization of coronary arteries wherein an inner catheter (50) andouter catheter (52) are used in combination for the treatment of rightand left coronary angiographic procedures. See also U.S. Pat. No.4,935,017 which discloses a similar device. U.S. Pat. No. 5,290,229discloses a straight outer sheath and a preformed inner catheter for usein the heart. See also U.S. Pat. Nos. 5,304,131, 4,810,244 and5,279,546.

U.S. Pat. No. 5,476,495 discloses a shaped guide sheath (166) for use inthe right ventricle for ablation procedures.

Ablation procedures in the heart using a single, straight guide sheathhave been disclosed. For example, catheter ablation of accessorypathways using a long vascular sheath by means of a transseptal orretrograde approach is discussed in Saul, J. P., et al. “CatheterAblation of Accessory Atrioventricular Pathways in Young Patients: Useof long vascular sheaths, the transseptal approach and a retrograde leftposterior parallel approach” J. Amer. Coll. Card., Vol. 21, no. 3, pps571-583 (Mar. 1, 1993). See also Swartz, J. F. “RadiofrequencyEndocardial Catheter Ablation of Accessory Atrioventricular PathwayAtrial Insertion Sites” Circulation, Vol. 87, no. 2, pps. 487-499(February, 1993).

In addition, U.S. Pat. No. 5,427,119 discloses a shaped guidingintroducer for introduction of an ablation and mapping catheter into theright atrium for the treatment of specific cardiac arrhythmia. U.S. Pat.No. 5,497,774 discloses the use of a guiding introducer for introductionof an ablation and mapping catheter into the left atrium for thetreatment of specific cardiac arrhythmia.

U.S. Pat. No. 4,641,649 discloses the use of high frequency energy forthe treatment of tachycardia or cardiac dysrhythmia. See also U.S. Pat.Nos. 5,246,438 and 4,945,912, which disclose the use of radio frequencyenergy for ablation of cardiac tissue. In addition, various articleshave disclosed the ablation of specific locations within the heart byuse of energy, in particular, radio frequency energy. See, for example,Gallagher, J. J. et al. “Catheter Technique for Closed-Chest Ablation ofthe Atrioventricular Conduction System” N. Engl. J. Med. Vol. 306, pp.194-200 (1982); Horowitz, L. N. “Current Management of Arrhythmia” pp.373-378 (1991); Falk, R. H. et al. “Atrial Fibrillation Mechanics andManagement” pp. 359-374 (1992); and Singer, I. “Clinical Manual ofElectrophysiology” pp. 421-431 (1993).

In addition, U.S. Pat. No. 5,172,699 discloses a general process for theidentification and ablation of ventricular tachycardia sites. See alsoU.S. Pat. Nos. 5,222,501 and 5,242,441.

In addition, the use of radio frequency ablation energy for thetreatment of Wolff-Parkinson-White Syndrome in the left atrium by use ofa transseptal sheath is disclosed in Swartz, J. F. et al.“Radiofrequency Endocardial Catheter Ablation of AccessoryAtrioventricular Pathway Atrial Insertion Sites” Circulation 87:487-499(1993). See also Tracey, C. N. “Radio Frequency Catheter Ablation ofEctopic Atrial Tachycardia Using Paced Activation Sequence Mapping” J.Am. Coll. Cardiol. 21:910-917 (1993).

While a number of references have disclosed ablation procedures in theheart utilizing sheaths and catheters, there is still a need for newmethods for the introduction of ablation catheters to specific locationsin the heart, including specifically the left ventricle.

Accordingly, it is an object of this invention to disclose a guidingintroducer system for selected medical procedures associated with theleft ventricle of the human heart.

It is a further object of this invention to disclose a guidingintroducer system for use in selected electrophysiology proceduresassociated with the left ventricle of the human heart.

Another object of this invention is to disclose a guiding introducersystem for use in selected ablation procedures associated with the leftventricle of the heart. It is a still further object of this inventionto disclose a guiding introducer system for use in the selected ablationof sites associated with the mitral valve from the ventricular side forthe treatment of left ventricular tachycardia.

These and other objects are obtained by the design of the guidingintroducer system disclosed in the instant invention.

SUMMARY OF INVENTION

The instant invention is a guiding introducer system for use in thetreatment of left ventricular tachycardia from the ventricular side. Itmay also be used to ablate locations under the mitral valve from theventricular side, for example, for the treatment ofWolff-Parkinson-White syndrome (“WPW”). It is comprised of a precurved,inner guiding introducer and a precurved, outer guiding introducer. Aprecurved dilator is preferably used with the guiding introducer system,which dilator is preferably used with a Brockenbrough needle. The innerguiding introducer is comprised of a first and second section, whereinthe first section is a generally elongated straight section which ismerged at its distal end with the second section, which is a curvedsection. The outer guiding introducer is comprised of a first and secondsections, wherein the first section is a generally elongated straightsection which is merged at its distal end with the second section whichforms a compound curved section. The inner guiding introducer is longerthan the outer guiding introducer to permit it to extend out from thelumen of the outer guiding introducer to form various curves and shapesof the overall guiding introducer system.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a cross-section of the left side of the heart showing theplacement of the guiding introducer system in the left ventricle withthe distal end of an ablation catheter extending from the distal end ofthe outer guiding introducer to ablate in three different locationsalong the walls of the left ventricle.

FIG. 1B is a cross-section of the left side of the heart showing theplacement of the guiding introducer system in the left ventricle withthe distal end of an ablation catheter extending from the distal end ofthe outer guiding introducer to ablate in two different locations underthe mitral valve.

FIG. 2A is a side view of the inner and outer guiding introducers incombination with the distal end of the inner guiding introducer extendedfrom the distal end of the outer guiding introducer.

FIG. 2B is a side view of the inner and outer guiding introducers incombination as shown in FIG. 2A rotated 90 degrees from the positionshown in FIG. 2A when viewed from the perspective of the proximal end ofthe inner and outer guiding introducers.

FIG. 3A is a side view of the inner guiding introducer attached to ahemostasis valve and side port with the side port directed to the leftof the inner guiding introducer.

FIG. 3B is a side view of the inner guiding introducer of FIG. 3Arotated 90 degrees clockwise from the position shown in FIG. 3A whenviewed from the perspective of the proximal end of the inner guidingintroducer.

FIG. 4A is a side view of the outer guiding introducer attached to ahemostasis valve and side port with the side port directed to the leftof the outer guiding introducer.

FIG. 4B is a side view of the outer guiding introducer of FIG. 4Arotated 90 degrees clockwise from the position shown in FIG. 4A whenviewed from the perspective of the proximal end of the outer guidingintroducer.

DESCRIPTION OF THE INVENTION

A typical human heart includes a right ventricle, a right atrium, leftventricle and left atrium. The right atrium is in fluid communicationwith the superior vena cava and the inferior vena cava. Theatrioventricular septum separates the atria from the ventricles. Thetricuspid valve contained within the atrioventricular septumcommunicates the right atrium with the right ventricle. The mitral valvecontained within the atrioventricular septum communicates the leftatrium with the left ventricle. On the inner wall of the right atrium,where it is connected with the left atrium, is a recessed portion, thefossa ovalis. Between the fossa ovalis and the tricuspid valve is theopening or ostium for the coronary sinus. The coronary sinus is a largeepicardial vein which accommodates most of the venous blood which drainsfrom the myocardium into the right atrium.

In the normal heart, contraction and relaxation of the heart muscle(myocardium) takes place in an organized fashion as electrochemicalsignals pass sequentially through the myocardium from the atrial to theventricular tissue along a well defined route which includes theHis-Purkinje system. Initial electric impulses are generated at thesinoatrial (SA) node and conducted to the atrioventricular (AV) node.The AV node lies near the ostium of the coronary sinus in theinteratrial septum in the right atrium. The His-Purkinje system beginsat the AV node and follows along the membranous interatrial septumtoward the tricuspid valve through the atrioventricular septum and intothe membranous interventricular septum. At about the middle of theinterventricular septum, the His-Purkinje system splits into right andleft branches which straddle the summit of the muscular part of theinterventricular septum.

Sometimes abnormal rhythms occur in the heart which are referred to asarrhythmia. For example, patients diagnosed with WPW have an arrhythmia,the cause of which is believed to be the existence of an anomalousconduction pathway or pathways that connect the atrial muscle tissuedirectly to the ventricular muscle tissue, thus by-passing the normalHis-Purkinje system. These pathways are usually located in the fibroustissue that connects the atrium and the ventricle.

Another arrhythmia is ventricular tachycardia (“V.T.”). VT is a diseaseof the ventricles of the heart in which the heart's normal arrhythmiccontraction is altered. Frequently, the rate of heart beat is too fast,although the conditions of the disease itself are generally quitecomplex. VT occurs most often in patients following a myocardialinfarction. A myocardial infarction, commonly referred to as a heartattack, is a loss of blood to a region of the heart causing themyocardial tissue in that region to die and be replaced by an area ofscar tissue known as a myocardial infarct. Frequently, the myocardialinfarct is present in the left ventricle.

As a result of the myocardial infarct, circular pathways (“reentrycircuits”) are frequently created within the left ventricle whichconduct electrical impulses of the heart. These reentry circuits causethe electrical impulses of the heart to travel in circles about themyocardial infarct, frequently causing an erratic and sometimesaccelerated beating of the heart. These reentry circuits may also occuraround discreet elements of the heart, such as valves. In addition, thereentry circuits sometime occur around both the myocardial infarct andthe discreet elements of the heart.

In the past arrhythmia have been generally treated by the use of drugs,such as lidocaine, quinidine and procainamide. More recently,beta-blocking drugs have been used for this treatment. In cases wheredrug therapy has been ineffective, surgical procedures have sometimesbeen used to excise the tissue causing the arrhythmia. The procedureinvolves the removal of a portion of the heart muscle, particularly thatportion around which the reentry circuit has formed. By the excision ofthis portion of the heart muscle, scar tissue is formed which preventsthe reformation of the reentry circuit. Obviously such procedures arehigh risk, frequently requiring prolonged periods of hospitalization andrecuperation. As an alternative to these procedures, ablation deviceshave been used for the diagnosis and treatment of cardiac arrhythmias.See, for example, U.S. Pat. No. 5,222,501. Also, guiding introducershave been used to guide ablation catheters for the treatment of atrialarrhythmias in U.S. Pat. Nos. 5,497,724 and 5,427,119.

Ablation procedures, however, are frequently unsuccessful unlessrepeated many times. It is presumed that one reason for the lack ofsuccess of ablation of ventricular tissue is the failure to destroycompletely the reentry circuit in the ventricular tissue because of itsinherent thickness and the size of the reentry circuit itself. Toeffectively ablate the ventricular tissue, the ablation catheter must bepositioned precisely within the ventricle and maintained in contact withthe ventricular tissue throughout the ablation procedure. Suchprocedures may require the ablation electrode of the ablation catheterto remain in contact with the ventricular tissue for a period of timewell over a minute. This is particularly difficult when the heart isbeating, sometimes irregularly, during the entire ablation procedure.Thus, it is critical that the ablation electrode be maintained at thedesired location and also be constrained from movement throughout theablation procedure.

Historically, there are two approaches to the positioning of an ablationcatheter in the left ventricle for ablation procedures. The firstapproach is to introduce the catheter into the femoral artery using astandard introducer and advance it up the aorta, across the aortic valveinto the left ventricle and then position its electrode adjacent to awall of the left ventricle. This is commonly referred to as a“retrograde” approach. This approach is discussed in patent applicationSer. No. 08/388,800 filed Feb. 14, 1995 and patent application Ser. No.08/389,252 filed Feb. 16, 1995. Specific locations for the mapping orablation of the ventricular tissue, include locations on the lateralfreewall, posterior freewall, septal wall and anterior freewall. Theretrograde approach to the left ventricle for ablation procedures isfrequently difficult for many reasons including the structure of theleft ventricle, the fact that it requires arterial access and potentialproblems associated with ablation of ventricle tissue, such as thecreation of a substrate for a future arrhythmia which could result insudden cardiac death. Thus, this retrograde approach is not preferred.

A second approach to positioning an ablation catheter for treatment ofarrhythmia located in the left ventricle is from the atrial side of themitral valve. This approach is referred to as the transseptal approachas the ablation catheter passes through the interatrial septum betweenthe right and left atria. In this procedure, a transseptal sheathapparatus, comprising a conventional transseptal introducer, such as isproduced by Daig Corporation, is introduced into the right femoral veinand advanced through the inferior vena cava into the right atrium. Apuncture is then made through the interatrial septum, preferably at thefossa ovalis, and the apparatus is then advanced into the left atriumwhere the needle and dilator of the apparatus are removed leaving theintroducer in place in the left atrium. An ablation catheter is thenadvanced through this introducer adjacent to or through the mitral valvefor treatment of various arrhythmia associated with the left ventricle.

Mere introduction of the ablation and mapping catheter into the leftventricle is not sufficient to effectively and efficiently perform theablation procedures to eliminate arrhythmia located in the leftventricle. The medical practitioner commonly monitors the introductionof the catheter and its progress through the vascular system by afluoroscope. Such fluoroscopes can not easily identify the specificfeatures of the heart in general, and the critically importantstructures associated with the left ventricle in specific, thus makingplacement of the ablation electrode difficult. This placement isespecially difficult as the beating heart is in motion. As a result, thecatheter is moving within the chambers of the heart as blood is beingpumped through the heart throughout the procedure. The guidingintroducer system of the instant invention addresses and solves theseproblems.

Referring now to FIGS. 1 through 4, the guiding introducer system of thepresent invention for procedures in the left ventricle for the treatmentof arrhythmia associated with the mitral valve from the ventricularside, such as WPW, and various ventricle tachycardia is comprised of aninner and outer guiding introducer. See FIGS. 1A, 1B, 2A and 2B. Eachintroducer is divided into a first and second sections. (Each section ispreferably formed as an integral portion of the entire guidingintroducer without discrete divisions. However, the division of eachguiding introducer into different sections better illustrates theoverall shape of the guiding introducers.) Each of the guidingintroducers will be shown in two views. See FIGS. 3A, 3B, 4A and 4B. Ineach of the views for ease of analysis, the guiding introducer will besecured to a hemostasis valve with side port for attachment toconventional side port tubing and a stop cock. In each such arrangement,the shape of the guiding introducer and each of its sections will bedescribed, making reference to its position in relation to the side portwhich is attached to the proximal end of the guiding introducer.

The guiding introducer system for use in the left ventricle is comprisedof an inner and an outer guiding introducer. See FIGS. 2A and 2B. Adilator is also preferably used, wherein the dilator preferably is atransseptal dilator used with cardiac procedures requiring aBrockenbrough needle for a transseptal puncture. Generally the distalend of the dilator is curved in a curve with an arc of about 20 to about70 degrees ending in its distal tip. The overall length of the dilatoris conventional.

The inner guiding introducer is generally comprised of two sections. SeeFIGS. 3A and 3B. The first section is a conventional generallyelongated, hollow straight section of sufficient length for introductioninto the patient and for manipulation from the point of insertion to thespecific desired location within the heart. Merged with the distal endof the first section of the guiding introducer, but an integral part ofthe entire guiding introducer, is the second section which is a curvedsection, curved with a radius of about 0.5 to about 1.5 in., preferablyfrom about 0.7 to about 1.3 in. and most preferably about 0.9 to about1.1 in. to form an arc of approximately 45 to about 135 degrees,preferably about 60 to about 120 degrees, and most preferably about 70to about 110 degrees ending in a distal tip.

The outer guiding introducer for use in the left ventricle is comprisedof a first and second sections. See FIGS. 4A and 4B. The first sectionis a conventional, generally elongated hollow straight section ofsufficient length for introduction into the patient and for manipulationfrom the point of insertion to the specific desired location within theheart. Merged with the distal end of the first section of the guidingintroducer is the second section which is preferably a compound curvedsection curving first in a first curved portion with a radius of about0.5 to about 1.5 in., preferably from about 1.0 to about 1.4 in., andmost preferably about 1.1 to about 1.3 in. with an arc of approximately10 to about 50 degrees, preferably about 10 to about 30 degrees and mostpreferably about 15 to about 25 degrees. Following the first curvedportion is the second curved portion which curves with a radius of about0.5 to about 1.5 in., preferably from about 0.7 to about 1.3 in., andmost preferably about 0.9 to about 1.1 in. with an arc of approximately135 to about 225 degrees, preferably from about 170 to about 210 degreesand most preferably about 180 to about 200 degrees ending in the distaltip of the outer guiding introducer. Preferably, the first and secondcurved portions are generally co-planar, preferably within about 20degrees of being within the same plane. As an alternative to thecompound curved section, a single curved portion may be used wherein theradius of this single curved portion is from about 0.5 to about 1.5 in.,preferably from about 0.8 to about 1.2 in. and most preferably about 0.9to about 1.1 in. with an arc from about 145 to about 260 degrees,preferably from about 180 to about 240 degrees and most preferably about200 to about 220 degrees ending in the distal tip of the second sectionof the outer guiding introducer.

While the above described shapes are preferred, the shape of thesections of each guiding introducer of the guiding introducer system maybe modified by use of one or more straight or curved sections as long asthe overall, general shape of each of the guiding introducers isapproximately as described above. In addition, the particular order ofthe curves may be changed as long as the overall curvature of each ofthe guiding introducers delivers the mapping and ablation catheter toapproximately the same location as the guiding introducer system abovedescribed as the preferred embodiment. Further, one or more curves ofthe guiding introducers may be combined or split into additional curvedor curved and straight sections as long as the general overall shape ofthe precurved, guiding introducers is maintained.

The design feature of the guiding introducer system provides a stableplatform supported by the cardiac anatomy to permit an ablation ormapping catheter to be advanced and withdrawn without the need forrepositioning the guiding introducer system. By extending the distal tipof the inner guiding introducer away from the distal tip of the outerguiding introducer and by rotating the inner guiding introducer withrespect to the outer guiding introducer, a variety of shapes of theguiding introducer system are formed to direct the mapping and/orablation catheter toward a particular site within the left ventricle.See FIGS. 1A and 1B where the distal end of the inner guiding introduceris rotated and/or extended to permit the ablation catheter containedtherein to ablate various locations within the left ventricle. Theseshapes permit ablation procedures to be performed in the left ventricleassociated with the mitral valve annulus from the ventricular side, forexample, in a position anterior to anterolateral to lateral toposterolateral to posteroseptal to septal to the mitral valve. See FIG.1B. In addition, by adjusting the extension and direction of the innerguiding introducer within the outer guiding introducer, ablation andmapping catheters can be directed for procedures on the left ventricularanterior free wall and toward the septal wall for treatment of BelhassenTachycardia. See FIG. 1A. The various locations can be treated byextending the inner guiding introducer further from the outer guidingintroducer which forms a different overall shape and/or by rotating theinner guiding introducer with respect to the outer guiding introducer.Being able to extend the inner guiding introducer within the outerguiding introducer and to rotate the inner guiding introducer within theouter guiding introducer permits a wide variety of overall shapes, whichis particularly useful to medical practitioners. The medicalpractitioner is able to determine the relative location of the inner andouter guiding introducers because of tip markers located near the distaltip of both the inner and outer guiding introducers.

The distal tip of both the inner and outer guiding introducers may be,and generally will be, tapered to form a good transition with thedilator.

The relative size of the outer guiding introducer in relation to theinner guiding introducer should be sufficient to permit the innerguiding introducer to be torqued or rotated within the outer guidingintroducer without undue restriction on such movement. Preferably, thedifference in size between the inner and outer guiding introducer shouldbe at least about 3 “French” (1 French equals about one-third of amillimeter). For example in one preferred embodiment, the outer guidingintroducer is 11 French in size and the inner guiding introducer is 8French. By this difference in diameter, there is approximately 1 Frenchunit of volume available between the outer surface of the inner guidingintroducer and the inner surface of the outer guiding introducer.Preferably, this volume of space between the inner and outer guidingintroducer is filled with a biocompatible solution, such as a salinesolution, preferably a heparinized saline solution. This saline solutionalso provides lubricity to the two guiding introducers, allowing moreaccurate torquing of the inner guiding introducer within the outerguiding introducer. In addition, it is preferable that the structure ofboth the inner and the outer guiding introducer have a high torsionalconstant to allow for the full utilization of the various shapesavailable by rotation and extension of the inner and outer guidingintroducer. To permit this high torsional constant, in one preferredembodiment the inner guiding introducer is braided to provide furtherstrength and structural stability.

The guiding introducers may be made of any material suitable for use inhumans, which has a memory or permits distortion from and subsequentsubstantial return to the desired three dimensional shape. For thepurpose of illustration and not limitation, the internal diameter of thetip of the guiding introducers may vary from about 6 to about 10“French” Such guiding introducers can accept dilators from about 6 toabout 10 French and appropriate guidewires. Obviously if larger, orsmaller dilators and catheters are used in conjunction with the guidingintroducers of the instant invention, modification can be made in thesize of the instant guiding introducers.

The inner and outer guiding introducers also preferably contain one or aplurality of vents near the distal tip of the guiding introducers,preferably 3 or 4 of such vents. The vents are preferably located nomore than about 5 to 6 cm. from the tip of the guiding introducers andmore preferably 0.5 cm. to about 4.0 cm. from the tip. The size of thesevents should be in the range of about 20 to 60 1/1000 of an inch indiameter. These vents are generally designed to prevent air embolismsfrom entering the guiding introducers caused by the withdrawal of acatheter contained within the guiding introducers in the event thedistal tip of one of the guiding introducers is occluded. For example,if the tip of the inner guiding introducer is placed against themyocardium and the catheter located within the inner guiding introduceris withdrawn, a vacuum may be created within the inner guidingintroducer if no vents are provided. If such vacuum is formed, air maybe forced back into the guiding introducer by the reintroduction of acatheter into the lumen of the guiding introducers. Such air embolismcould cause problems to the patient including the possibility of astroke, heart attack or other such problems common with air embolisms inthe heart. The addition of vents near the distal tip of the guidingintroducers prevents the formation of such vacuum by permitting fluid,presumably blood, to be drawn into the lumen of the guiding introducersas the catheter is being removed, thus preventing the possibility offormation of an air embolism.

Variances in size or shape of the pair of guiding introducers are alsointended to encompass pediatric uses, although the preferred use is foradult human hearts. It is well recognized that pediatric uses mayrequire reductions in size of the various sections of the guidingintroducers in particular the first section, but without any significantmodification to the shape or curves of the guiding introducers. However,because incremental changes can be made in the overall shape of the pairof guiding introducers, the system can better adjust to differing shapesand sizes of heart than can a single guiding introducer.

In operation, a modified Seldinger technique is normally used for theinsertion of a catheter into either an artery or vein of the body. Usingthis procedure, a small skin incision is made at the appropriatelocation to facilitate the catheter and dilator passage. A soft flexibletip of an appropriate sized guidewire is inserted through and a shortdistance beyond a needle which has been introduced into the vessel.Firmly holding the guidewire in place, the needle is removed. Theguidewire is then advanced through the vessel into the right atrium.With the guidewire in place, a dilator is then placed over the guidewirewith the pair of guiding introducers placed over the dilator. Thedilator and pair of guiding introducers generally form an assembly to beadvanced together along the guidewire into the right atrium. Afterinsertion of the assembly, the guidewire is then withdrawn. ABrockenbrough or trocar needle is then inserted through the lumen of thedilator to the right atrium to be used to create an opening through theinteratrial septum, preferably at the fossa ovalis. The tip restsagainst the interatrial septum at the level of the fossa ovalis. TheBrockenbrough needle is then advanced within the dilator to the fossaovalis. After the opening is made through the interatrial septum, theneedle, dilator and pair of guiding introducers are advanced into theleft atrium. After the pair of guiding introducers are advanced throughthe interatrial septum into the left atrium, the Brockenbrough or trocarand dilator are removed, leaving the pair of guiding introducers in theleft atrium. The distal tips of the inner and outer guiding introducersare then advanced through the mitral valve into the left ventricle. Thecatheter to be used for analysis and/or treatment of the ventriculartachycardia or other arrhythmia associated with the left ventricle, suchas WPW, about the mitral valve is then advanced through the lumen of thepair of guiding introducers and is placed at an appropriate location inthe left ventricle. See FIG. 1. By extending and withdrawing the innerguiding introducer from the outer guiding introducer and by rotating theinner guiding introducer within the outer guiding introducer, greatvariances in the overall shape of the guiding introducer system can beachieved.

By movement of the inner guiding introducer within the outer guidingintroducer in conjunction with fluoroscopic viewing, the distal portionof the inner guiding introducer can be manipulated to direct the distalend of a catheter to a specific internal surface within the leftventricle. See FIGS. 1A and 1B. In addition, by providing sufficientrigidity, the distal end of the inner guiding catheter can be maintainedin that fixed location or surface position of the endocardial structureto permit it to act as a stationary platform for the appropriateprocedures to be performed. If sensing procedures are involved, the pairof guiding introducers are placed in the desired location. At thatpoint, the electrical activity of the heart peculiar to that locationcan be precisely determined by use of an electrophysiology catheterplaced within the guiding introducers and extended from the distal tipof the inner guiding introducer to the surface of the heart. As the pairof guiding introducers permit precise location of catheters, an ablationcatheter may be placed at the precise location necessary for destructionof the cardiac tissue by the use of energy, for example, radiofrequency, thermal, laser or direct current (high energy direct, lowenergy direct and fulgutronization procedures). The precise placement ofthe ablation catheter tip on the cardiac tissue is important as therewill be no dilution of the energy delivered due to unfocused energybeing dissipated over the entire cardiac chamber and lost in thecirculating blood by constant movement of the tip of the ablatingcatheter. This permits a significantly reduced amount of energy to beapplied, while still achieving efficient ablation. Further, time used toperform the procedure is significantly reduced over procedures where noguiding introducers are used.

It will be apparent from the foregoing that while particular forms ofthe invention have been illustrated and described, various modificationscan be made without departing from the spirit and scope of theinvention. Accordingly, it is not intended that this invention belimited except as by the appended claims.

1. A guiding introducer system for treatment of arrhythmia associatedwith the left ventricle from the ventricular side comprising a precurvedinner guiding introducer and a precurved outer guiding introducerwherein said guiding introducers are used in combination.
 2. The guidingintroducer system of claim 1 wherein a dilator containing distal andproximal ends is used in conjunction with the inner and outer guidingintroducers, wherein said dilator curves at its distal end in a curvewith an arc of about 20 to about 70 degrees.
 3. The guiding introducersystem of claim 1 wherein the inner guiding introducer comprises a firstand second sections each with proximal and distal ends, wherein thefirst section is a generally elongated straight section, wherein mergedwith the distal end of said first section is the second section whichcontains a curved section with a radius of about 0.5 to about 1.5 in. toform an arc of approximately 45 to 135 degrees ending in the distal endof the second section of the inner guiding introducer.
 4. The guidingintroducer system of claim 1 wherein the outer guiding introducercomprises a first and second sections each with proximal and distalends, wherein the first section is a generally elongated straightsection, wherein merged with the distal end of said first section is thesecond section which contains a curved portion, curving in a radius ofabout 0.5 to about 1.5 in. to form an arc of about 145 to about 260degrees, ending in the distal end of the second section of the outerguiding introducer.
 5. The guiding introducer system of claim 1 whereinthe outer guiding introducer comprises a first and second section eachwith proximal and distal ends, wherein the first section is a generallyelongated straight section, wherein merged with the distal end of thefirst section is the second section, wherein the second section containsa compound curved section containing a first curved portion and a secondcurved portion, wherein the first curved portion has a radius of about0.5 to about 1.5 inches and an arc of about 10 to about 50 degrees andthe second curved portion has a radius of about 0.5 to about 1.5 inchesand an arc of about 135 to about 225 degrees.
 6. The guiding introducersystem of claim 3 wherein a plurality of vents is provided near thedistal end of the second section of the inner guiding introducer.
 7. Theguiding introducer system of claim 4 wherein a plurality of vents isprovided near the distal end of the second section of the outer guidingintroducer.
 8. The guiding introducer system of claim 3 wherein tipmarkers are secured to the inner guiding introducer.
 9. The guidingintroducer system of claim 4 wherein tip markers are secured to theouter guiding introducer.